Paperboard cartons are commonly used for packaging various types of food products such as milk and juice. Such food products are conventionally packaged in gable top cartons which are preformed with a closed bottom and upstanding walls. Typically, the cartons are placed on a conveyor which intermittently advances the cartons through a filling machine. Before the cartons are filled, however, it may be desirable to subject the cartons to various operations. For example, to increase the shelf life of food products, the interior of the carton can be subjected to a sterilizing operation. Sterilization of the carton can be effected by spraying a hydrogen peroxide solution into the interior of the carton.
After the cartons have been filled, they are advanced to a station in which the top portion of each carton is closed and sealed to result in a filled gable top carton. The carton is usually provided with several score lines which define the fold lines about which the top portion of the walls bend so as to form the gable top carton. To facilitate the proper folding (i.e., closing) of the carton walls, it is oftentimes desirable to prebreak the score lines on the carton (i.e., break the score lines before they are folded and sealed at the closing and sealing station). In that way, once the cartons reach the stage in which the upstanding carton walls are folded and sealed, the carton is much less susceptible to being improperly folded and sealed.
It can be readily appreciated, however, that if the aforementioned sterilizing and score line breaking operations are positioned at successive stations within the filling machine so as to require that the carton be advanced from one station in which the carton score lines are broken to another station in which the carton is sterilized, additional space will be required within the filling machine. In the case of existing machines, space constraints may not allow both operations to be carried out at successive stations. Thus, if limited to positioning the two operations at successive stations, it may not be possible to perform both operations in the filling machine.